Nuclear stability is derived from the brane-bulk framework as a competition between the strong-force closure condition (H−associator [e4,e5,e6] = -2e7 favouring colour-neutral combinations) and the electrostatic repulsion (H+ radial wave mode, pro- portional to Z2). The iron stability maximum at A = 56 is the conguration that minimises the sum of strong-force binding energy and electrostatic energy per nucleon an "iron attractor" in the space of nuclear congurations. Radioactive decay modes (α, β, γ) are the three pathways back toward the iron attractor from congurations that are too large (α decay), have wrong n/p ratio (β decay), or are excited (γ decay). The time-varying Chandrasekhar mass M_Ch(z) ∝H(z)6 is derived here as a consequence of ℏ(t) ∝H(t)3 and c(t) ∝H(t), with the prediction that super-Chandrasekhar collapses occurred at z = 5-10, generating the Little Red Dot BH seeds.Part of the One-Octonion Brane-Bulk Framework series. Anchor DOI: 10.5281/zenodo.19120873. Community: one-octonion-brane-bulk. Author: Bharathi Dasan Jagadeesan, M.D., University of Minnesota. ORCID: 0000-0002-1143-941X.